A.—sc.

3. The safe working load at any radius specified in the most recent certificate— (а) Shall not be more than 80 per cent, of the maximum load which the crane has stood at that radius during the application of the test; and (б) Shall not be greater than the working load indicated by the maker. 31. Regulation.—Derrick Cranes. 1. The maximum radius at which the jib may be worked shall be clearly indicated on every derrick crane. 2. When the jib is at the maximum radius there shall not be less than two dead turns of rope on the derricking-drum. 3. The jib of a Scotch derrick crane shall not be erected between the back-stays of the crane. 4. Every crane having a derricking-jib shall be provided with an effective interlocking arrangement between the derricking-clutch and the pawl sustaining the derricking-drum, except where — (a) The hoisting-drum and the derricking-drum are independently driven ; or (b) The mechanism driving the derricking-drum is self-locking. 5. Where the guys of a guy derrick crane cannot be fixed at approximately equal spacing, such other measures shall be taken as will ensure the safety of the crane. 6. The whole of the appliances for the anchorage of a crane shall be examined on each occasion before the crane is erected. 7. The erection of cranes shall be supervised by a competent person. 8. Each crane shall after each erection on a building-site and before use be tested in situ for anchorage by a competent person. 9. Cranes shall be tested for anchorage by the imposition on each anchorage of the maximum uplift or pull exerted either — (а) By a load of 25 per cent, above the maximum load to be lifted by the crane as erected; or (б) By a less load arranged to exert an equivalent pull on the anchorage. 10. If the puli applied by the test to any anchorage is less than 25 per cent, in excess of the pull which would be exerted by the maximum safe working load, a loading-diagram appropriate to the crane anchorage shall be affixed in a position where it can readily be seen by the crane-driver. Regulation 32. — Automatic Safe Load Indicators. 1. No jib crane whether having a fixed jib or a derricking-jib shall be used unless it is fitted with an automatic indicator which — (а) Indicates clearly to the driver or person operating the crane when the load being moved approaches the safe working load of the crane at any inclination of the jib ; and (б) Gives an efficient sound signal when the load being moved is in excess of the safe working load of the crane at any inclination of the jib. 2. The preceding paragraph does not apply to — (a) Any guy derrick crane ; (b) Any hand crane which is being used solely for erecting or dismantling another crane ; or (c) Any crane having a maximum safe working load of 1,000 kg. or less, but in all such cases a table showing the safe working loads at various radii of the jib shall be kept attached to the crane. Regulation 33. —Various Rules concerning Crane Operation. ]. (1) A crane shall not be used otherwise than for direct lifting or lowering of a load unless its stability is not thereby endangered. (2) No load which, lies in the angle between the backstays of a Scotch derrick crane shall be moved by that crane. 2. Where more than one crane or winch is required to lift or lower one load — (a) The machinery, plant, and appliances used shall be so arranged and fixed that no such crane or winch shall at any time be loaded beyond its safe working load or be rendered unstable in the hoisting or lowering of the load ; and (b) A person shall be specially appointed to co-ordinate the operation of the appliances working together. 3. When a load is thought to approach the maximum safe working load a trial shall be made by raising the load a short distance to ensure that the hoisting appliance can carry it safely. Regulation 34. —Hoists. 1. Hoists (i.e., lifting appliances provided with a cage or platform that runs in guides) used for raising and lowering materials shall satisfy the requirements of this regulation. 2. (1) Hoist shafts shall be provided with solid walls or other equally effective fencing — (a) At the ground level on all sides ; and (b) At all other levels on all sides to which access is provided. (2) The walls of hoist shafts, except at approaches, shall extend at least 2 m. above the floor, platform, or other place to which access is provided.

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